Purpose – The purpose of this paper is to investigate the effects of thermal radiation and viscous dissipation on steady natural convection flow of a viscous incompressible fluid along a uniformly moving infinite vertical porous plate with Newtonian heating in the presence of transverse magnetic field. The governing non-linear boundary layer equations are solved by using homotopy analysis method (HAM). The effects of various system parameters on velocity and temperature fields are discussed graphically, and the numerical values for skin friction and Nusselt number are presented in tabular form. Design/methodology/approach – The problem is formulated using the Boussinesq approximation under the effects of thermal radiation and transverse magnetic field. The resulting coupled system of non-linear differential equations is solved using HAM with appropriate boundary conditions for Newtonian heating of the plate. HAM is a powerful method which provides rapidly converging series solution for the velocity and temperature fields. The effects of Prandtl number, Grashof number, suction parameter, magnetic field parameter, radiation parameter and Eckert number on the fluid velocity, temperature, skin friction and Nusselt number have been investigated. Findings – The HAM solution has been successfully applied to find the converging series solution for velocity and temperature fields in terms of pertinent system parameters. Comparison of the exact solution results agree well with the HAM solution results in the absence of Eckert number and this indicates that the HAM solutions are accurate. It is found that the velocity and temperature profiles decreases with the increase of thermal radiation and suction parameters. An increase in the magnetic field parameter leads to a rise in the fluid temperature and fall in the fluid velocity. Research limitations/implications – The present analysis is limited to steady state laminar natural convection flow only. Unsteady natural- /mixed-convection laminar flow in the presence of thermal radiation, chemical reaction and transverse magnetic field will be investigated in a future work. Practical implications – The study provides very useful information for heat transfer engineers to understand the heat transfer rate when the moving vertical porous surface temperature is not known a prior. The present results have immediate relevance in the design of nuclear reactors where vertical moving porous plates are using as control rods. Originality/value – The present research work is relatively original and illustrates the effects of thermal radiation, viscous dissipation and transverse magnetic field on natural convection flow past a uniformly moving infinite vertical porous plate with Newtonian heating.

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This research deals with an analysis of the Hall current effect on the mixed convective magneto-micropolar fluid flow over a permeable stretching/shrinking sheet. Impact of the Newtonian heating parameter is analyzed in the slip flow regime. The nonlinear equations of the fluid flow are derived with the help of a similarity transform and its solutions are obtained by Optimal Homotopy Analysis Method (OHAM). For limiting cases, obtained results are in excellent agreement with the available exact and numerical results in the literature. The graphical and tabular representations of the obtained results show significant effects of the physical parameters on the magneto-micropolar fluid flow and heat transfer characteristics. In particular, it is observed that, as the sheet stretches, a change in the Hall current parameter yields a higher horizontal velocity component for the lower value of the magnetic field parameter; while it produces a higher and shorter transverse velocity profile at high intensity of the magnetic field. In Magnetohydrodynamics (MHD) generators, Hall effects are an important consideration to analyze the heat transfer phenomenon with high temperature conducting fluids.

The purpose of this study is to analyse the combined effects of the heat generation(source)/ absorption (sink) and Newtonian heating on the mixed convective micropolar fluid flow past over a stretching/shrinking porous sheet. Slip flow model is also taken into account in this investigation. The governing flow behaviour is designed by coupled partial differential equations and then transformed into a system of coupled nonlinear ordinary differential equations with the mixed derivative boundary conditions. A semi-analytical approach named Homotopy Analysis Method (HAM) is applied to solve this transformed system of nonlinear equations. Influences of the pertinent dimensionless parameters on the prescribed velocities and temperature profiles along with the physical quantities are presented in the graphical and tabular illustrations. For special cases, it is found that the obtained solutions are excellent in agreement with the available results. In this study, it is observed that when the sheet stretches or shrinks, the temperature of the micropolar fluid flow increases with an increase in the heat generation and Newtonian heating parameters and it decreases with an increase in the heat absorption parameter and the Prandtl number. This investigation of the heat generation and absorption on the micropolar fluid flow with slip flow effects has shown the useful information which could be helpful for crystal growing in the industry and the processes to polish the artificial heart valves and the internal cavities.

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